This invention is an improvement in the self-flaking sail system disclosed in, and this patent application incorporates by reference all material contained in U.S. patent application Ser. No. 07/376,316, titled Self-Flaking Sail System, filed Jul. 6, 1989 and subsequently issued as U.S. Pat. No. 4,986,205 on Jan. 22, 1991. Embodiments of the apparatus disclosed and claimed in the referenced patent application constitute certain of the elements of the combination of the present application.
The conventional method for furling a sail is to release tension applied to it and gather it manually by bunching, rolling or flaking. Significant, economically feasible improvements in this method have been essentially limited to various forms of bagging, wherewith sails are pulled into elongate bags disposed along masts or booms or carried by the sail itself, and to roller furling, wherewith sails are wrapped around booms or stays as the latter are rotated. Bagging systems relatively conveniently secure the sails and may be configured to do so without requiring crew members to expose themselves to hazards attending leaving a cockpit to furl sails; but the bagging systems are relatively expensive, complicated and can develop problems at inopportune moments.
Roller furling apparatuses also have the advantages of being relatively convenient to use and of not usually requiring that crew members leave the cockpit to furl a sail. Roller furling apparatuses, however, require relatively complicated hardware, are often unusable with boomed sails such as mainsails, often reduce the efficiency of sails because they influence the shapes thereof, and can sometimes introduce handling problems during heavy winds when rolled sails wrap tighter than normal, leaving a portion of the sails unfurled to catch the wind.
Sails that are lowered for manual furling present a problem of maintaining control of the sail as it loses vertical tension and descends. Efforts have been directed toward designing means for automatically flaking sails as they are lowered. An example of this is disclosed in U.S. Pat. No. 4,688,506 to van Breeme. The van Breeme boat sail control system includes one or more control lines vertically disposed between a sailboat boom and an associated topping lift. Each control line passes through vertically aligned holes in the sail and runs along alternately opposite sides thereof. As the sail is lowered, oppositely facing folds are alternately formed in the sail, flaking the sail over the boom as the sail descends.
Another example of a system designed to automatically flake a descending sail onto a boom is disclosed in U.S. Pat. No. 4,864,952 to Stevenson. The Stevenson marine sail system provides a number of luff slides flexibly connected, at spaced-apart points, to the luff of the sail in canted orientations that alternate from slide to slide to impart a flaking moment to the luff as the sail is lowered.
A like number of brails are connected between spaced-apart points along the leech of the sail and a topping lift, the brails being slidably attached to the topping lift to permit movement therealong as the sail is raised and lowered, the brails being attached to the leech at points that are opposite to points of attachment of associated luff slides to the luff.
While each of these sail flaking systems functions with a certain degree of efficiency, none disclose the advantages of the improved sail douser and leech control system of the present invention as is hereinafter more fully described.